<template>
	<div>
		<ul>
			<li v-for="(item,index) in arr" :key="index">
				{{item}}
			</li>
		</ul>
		<button @click="btn">下标1位置插入新来的</button>
	</div>
</template>

<script>
	export default {
	data(){
		return{
			arr:['老大','老二','老三']
		}
	},
	methods:{
		btn(){
			this.arr.splice(1,0,'新来的')
		}
	}
	}
</script>

<style>

</style>
